Pic. 6-12. Main cylinder leak test diagram: 1 - valve for pumping the stand; 2 - manometer; 3 - absorbing cylinder; 4 - main cylinder; 5 - flywheel, 6 - pusher offset indicator. 7 - crane; 8 - vessel
Open valves 1 to bleed the stand and, by moving the master cylinder pistons several times to their full stroke length, bleed the system. Then close the valves 1. By rotating the flywheel 5, slowly move the master cylinder pistons until the pressure controlled by the pressure gauges 2 reaches 12.5 MPa (125 kgf/cm2). In this position, block the pusher of the master cylinder. The specified pressure must remain constant for at least 5 s.
In case of fluid leakage or reduction of the set pressure within 5 s, replace the cylinder piston seals.